Russinovich’s second novel featuring computer genius Jeff Aiken improves on his first, Zero Day (2011). Jeff now runs a cyber-security company in Washington, D.C., aided by his love interest from the previous book, ex-NSA staffer Daryl Haugen. When a British intelligence officer in London receives a file sent by a U.N. worker in Geneva, Switzerland, that’s corrupted in new and highly dangerous ways, the Foreign Office turns to Jeff for help. The malware behind the hack, Jeff discovers, points to China, the source for most of the extremely sophisticated computer viruses in the world, including a program that will enable Iran to dodge the worst of the Stuxnet virus that has plagued their nuclear program. The kidnapping of Jeff and Daryl in Geneva by Iranian agents complicates the pair’s efforts to stop the Chinese code from reaching the Iranians. Russinovich makes the technical lingo easy to understand as he successfully builds an exciting thriller around people sitting in front of computer screens. (Sept.)